Improved fbiotion-clutch ptjllei



' @uitrit-gisten atrnt @fitte DAVID nAERlNeToNgoIE WORCESTER,MASSACHUSETTS, AssIeNoE To- HIM- sELE AND J. s. WHEELER AND COMPANY. 0E SAME PLAGE.

Letters Paten-t No. 78,961, dated June 16, 1868.

LMPEOVED rEIeToN-etoron PULLEY,

KNOW ALL 'MEN BY THESE PRESENTS:

That I, DVID HARRINGTON, of the city and county of Worcester, and Commonwealth of Massachusetts, have invented certain new and useful Improvements in Friction-Clutch Pulleys and I do hereby declare that the follow-ing is a'full, clear, and exact descriptionof the same, reference being hadzto the accompanying drawings, forming-'apart of this specitieationpinwhich- Figure lirepresents a. side view of my improved pulley as it appears when applied to use.

AFigure 2 represents/a. face view of the pulley, and

Figure 3 represents a longitudinal central section on line A B.

To enable those skilled in the art to which my invention belongs to make and use the same, I will proceed to describe it more in detail. l i

`A. very great number of' friction-clutch pulleys have been heretofore devised, but to all of them more or less objections exist. 1

My pulley .is designed to obviate the objections 4which ere urged against those friction-pulleys in common use.

In the drawings, A is.the pulley, composed of the hub B, curved centre or web-part C; and face or rim D.

The hub has a hole through its centre, to receive the spindle or shaft E, upon which the pulley turns loosely.

Upon the insideof the pulley is fitted to and fastened upon the shaft or spindle E a hub-piece, F, having two arnis, G Gr, one'on each side, which project' out towards the periphery or rim of" the pulley, and have on their outer ends projections H H, through`whieh the stems I I of the metal friction-pads J J pass. Pins a a project fromvtheouter ends of the arznsG G,'through holes Ain the friction-pads, as -indicated in fig. L3 of the drawings, thereby retaining the padsin theirpropler relative positions when operated.

Upon each side of hub F is fitted a short shaft, c,.having a rightfhand screw-thread cut on one end, and u left-hand screw-thread eut on the other;

The inner ends of the shafts c are screwed into screw-holes bored andztapped in the opposite sides of hub F, while the outer ends of the same shafts are fitted to work in screw-holes bored andtapped in the ends of the stems I I, all as fully indi'oated in the drawings.

Upon each shaft lc is placed-or slipped a crank-arm, L,` the same being secured in any desired position a set-screw, I). Each crank-arm L is connected to the sliding-hubpieee M by a hinged arm or connection, N.

Hub-pieee Millas aigroove, c, to receive the fork of the operating-lever, by which hub-pieee M is moved b'aclc and forth on the shaft E, to cause the serew-shafts K K to move the pads J J ont or in, to clamp the rim D of pulley A to the arms G G of the hubF, which is fastened securely to the shaft or spindle E. Hub-piece M is provided with a slot, d, to receive the spline or key f, fitted into the shaft E, whereby the hub M will always revolve with shaft E, while at the same time it is free to slide t hack land forth on the shaft, to operate the shafts KKfor the purposesvstated.

It will be observed that the connections NN are arrangedupon opposite sides of the hubs and F, whereby the balance of the parts is retained in a very uniform manner.

It is very often the case that two clutch-pulleys are used in connection with each other, that is, both pulleys are clutched by one lever, one being clutched when the other is freed, and in which case I have east-upon the huh M four projections or circular enlargements, g g, two, or one set, on each end, the groove e being lbetween each set, as fully shown' in the drawings.

VThe operation is as follows: Pulley A has a continuous motion imparted to it, and when it isldesred to drive shaft E by means of said pulley, the operator, by means of his shipping-levcr, forcesA hub M towards puli ley A, thereby turning the screw-shafts K K, throughthe instrumentalities of the hinged connecting-arms NN and crank-arms L L',.wl1'ereby the friction-pads J J are forced `out against the inner surface of the rim D with suicient force to securelybind and clamp the. armsG G and pulley A together. I t will be understood that when the screw-shafts K K are turned, the friction-pnds J J are forced out very rapidlv, even by a pnl-tial revolutionofthe screw-shafts K K, since the threads are se cut upon the ends ef' said shams tnnt, when turned, tbe ends in the hub F lscrew out, while at thesame time the stems I I are also screwed oil' from-the ends ofsaiil shafts, thus forcing the pads J J outl towards and against the rim of the wheel with the combined velocity of both screws.

A slight motion of the hub M from pulley A will withdraw the pads froui the rimlof the wheel, and leaver it free to revolve, without'turning arms G G, hub F, and shaft E.

In lieu of the connections N N and cranica-rms L L, for operating the shafts K K, the latter may beprovidedwith spur-gears,- to be operated with racks, hinged or connected to the projectiorisg g in the samen'mnne'r ,as the arms N N, or said racks may be connected to the hub M in any other proper manner.

The screw-shafts could be made with a screw-thread on only one end, the other end being fastened by a swivel-joint, but I prefer to make them as shown inthe drawings.l l

The 'hub F is fastened to shaft E by means of a sensoren', m, and a stop-screw, n, may be inserted in huh F to stop hub M, all as indicated inthe drawings.

My iniproved friction-clutch pulley is not liable to get out ot' order, can be operated quickly and easily, and, besides, can be conveniently adjusted to keep the friction-pads in their proper relative positions, so as to exert aiunform and comparatively even pressure upon opposite sides of the rim of the pulley.

In lieu of having both of the connections N N hinged or connected to the hub M, asingle T-urm may project from hub M, with short connections from the ends of the T te the crank-arms onvthe screws or shafts K K, and an` arrangement of a corti or ebainnay be made, so as to operate theserews or shafts K K by that.

Having described my improved frictionycluteh pulley, what I claim therein as new and of my invention, and desire to secure by Letters Patent, is

1. The combination, with the' rim D of the pulley, hub F, and arms G G, of' lthe screw-shafts K K and friction-pads J J, substantially as and for the purposes set forth.

2d. The combination, with the screw-shafts K K und hub vM, of the crank-arms I I `and connections N substantially as and for the purposes set forth.

3. The combination, with the hub M, of the projections gg, substantially as shown and described. 4. The combina-tion and relative arrangement, with the loose pulley A and shaft E, ofthe hub F, arms G G, with projections H H, and steady-pins a a, and screwshai`ts K K, substantially tis-:1nd for the purposes set forth.

DAVID HARRING'ION.

Witnesses Tiros. H. Dones, CuAs. H. BURLEIGH. 

